Indicative significance of water environment in zeolitic structure - a study using experimentally grown cancrinite and analcime

• Autorzy: Słaby E.
• Języki publikacji: EN

Abstrakty

EN

Cancrinite and analcime were synthesized in the two hydrothermal systems: acid plagioclase - Na2CO3 - H2O and basic plagioclase - Na2CO3 - H2O under widely varying temperatures and salt concentrations in the solution. The IR 1^H MAS NMR DTG/TG analyses were carried out to determine water position in the crystals. Additionally IR spectra were recorded during subsequent dehydration and rehydration processes. The results of the investigations indicate that the water environment in both minerals is sensitive to the conditions of crystal formation. Crystallization temperature is the most important factor influencing water position. The water sites in the analcime and cancrinite crystals depend on structure modifications. Variations of the structure result from different chemical composition of the source material, structure of the substrates and the salt concentration in the solution. The structures formed under lower temperatures incorporate more water than those formed at high temperatures. In the cancrinite and analcime two main types of water, H2O(I) and H2O(II) appear. Other OH[m] groups can also be recognized. The position of water H2O(II) is better defined than that of H2O(I). H2O(II)is the most sensitive indicator of thermal conditions of the formation of cancrinite as well analcime. The amount of H2O(II) equals thatof H2O(I) in the products of low temperature (300 stopni C) syntheses. In crystals synthesized at high temperature (550 stopni C) the presence of H2)(II) is very limited.

Słowa kluczowe

EN

analcime; cancrinite; crystallization

• Wydawca: Faculty of Geology of the University of Warsaw ; Komitet Nauk Geologicznych PAN
• Czasopismo: Acta Geologica Polonica
• Rocznik: 1999
• Tom: Vol. 49, no. 1
• Strony: 25--65
• Opis fizyczny: Bibliogr. 60 poz., tab.

Twórcy

autor

Słaby E.

• Institute of Geochemistry, Mineralogy and Petrology of the University of Warsaw, PL-02-089 Warszawa, Al. Żwirki i Wigury 93